The term Administrator in its general sense signifies a person who administers some common affairs, for a longer or shorter period, not in his own name or in virtue of the ordinary jurisdiction attached to a certain office, but in the name and by the authority of a superior officer by whom he is delegated. In this sense vicars, and prefects-apostolic, vicars-capitular and even vicars-general are sometimes classed as administrators. In the stricter sense, however, this term is applied by modern writers to a person, usually a cleric and but rarely a layman, to whom the provisional administration of certain ecclesiastical affairs is entrusted by special papal or episcopal appointment. Although in itself delegated, the power of an administrator may be quasi-ordinary with the right of subdelegating. Its extent depends entirely on the tenor of his commission. His jurisdiction may extend to temporalities only, or to spiritual matters exclusively, or it may comprise both. There are three kinds of administrators who deserve special mention: (1) Administrators of dioceses; (2) Administrators of parishes; (3) Administrators of ecclesiastical institutions.

(1) Administrators of dioceses

Inasmuch as these administrators are appointed only by the Apostolic See, the title of Administrator Apostolic applies principally to clergymen, bishops, or priests, who are appointed directly by the Holy See, with episcopal jurisdiction to administer the affairs, temporal, or spiritual, or both, of a diocese. Their power is very nearly the same as that of vicars, and prefects-apostolic. A provicar is in fact simply an administrator apostolic. Unless it be otherwise stated in the brief of appointment, the administrator apostolic has full episcopal jurisdiction, although in its exercise he is bound by the same laws as the bishop himself. Thus, for instance, in the United States the administrator of the diocese is bound to take the advice or to get the consent of the diocesan consultors, in the same manner as the bishop (III Pi. C. Balt., n. 22). For the event of his death, the administrator apostolic may designate in advance his own successor. His support must come from the diocese which he administers, unless otherwise provided for. While the jurisdiction of the administrator apostolic is similar to that of the bishop, yet his honorary rights are greatly limited. Even if he has episcopal orders, he cannot use the throne, nor the seventh candle, nor honorary deacons, although he has the right of the crosier. His name is not mentioned in the canon, nor is the anniversary of his consecration commemorated. Administrators apostolic may be appointed in two cases:

Sede impeditâ; that is, when the bishop of the diocese is unable any longer to administer the affairs of the diocese either through infirmity, insanity, imprisonment, banishment, or because of excommunication or suspension. In this case the jurisdiction of the administrator, though he were a simple priest, is the same as that of the bishop, who can no longer interfere in the affairs of the diocese. On the death of the bishop the administrator remains in office until recalled by Rome, or until the new bishop takes charge of the diocese;

Sede vacante, when a diocese which has no cathedral chapter becomes vacant by the resignation, or the removal, or the death of its bishop. Where there is a cathedral chapter it will in those cases elect a vicar-capitular to administer the diocese. Otherwise an administrator must be chosen or appointed who will provisionally administer the diocese until confirmed by the Holy See.

In missionary countries the bishop or vicar-apostolic may himself designate the future administrator of the diocese or vicariate. If he neglects to do so, after his death an administrator is appointed by the nearest bishop or vicar-apostolic, or, in the United States, by the metropolitan and in his absence by the senior bishop of the province. In China and East India, if no provision for a provicar is made by the vicar-apostolic, the priest longest in the mission becomes administrator apostolic of the vicariate. In case of doubt or other difficulties, the decision rests with the nearest vicar-apostolic. When a diocese becomes vacant by the resignation of the bishop, he may be appointed by Rome administrator of the same diocese until his successor take possession of it. When a diocese is divided, the bishop may become administrator of the new diocese, or, if transferred to the new diocese, become administrator of the old one, until a bishop is appointed for the vacant see.

(2) Administrators of parishes

Sometimes called parish vicars, curates, or coadjutors. They may be appointed for the same reasons as an administrator apostolic, namely, for a vacant parish, or during the lifetime of the rector or pastor who has become unfit for the administration of the parish, or during his absence for a longer period. Such an administrator is usually appointed by the bishop of the diocese, with full Jurisdiction over parish affairs and with a sufficient revenue for his support, which according to circumstances may be derived from the parish, or from the pastor, or from both. His office and jurisdiction cease either by recall or by appointment of a new pastor. In the United States, when an irremovable rector of a parish makes an appeal against his removal by the bishop, the bishop must appoint an administrator of the parish until the appeal is decided by the higher authority (III P1. C. Balt., n. 286). Among these parish administrators may be classed the so-called perpetual or permanent curates of parishes which are under the jurisdiction of some convent or monastery, and of which the rector or curate is appointed not by the bishop of the diocese, but by the superior of such convent. The case is far more frequent in Europe than in America. The charge of the parish is considered to be with the monastery, and the curate is merely the administrator of the parish for the convent.

(3) Administrators of Ecclesiastical Institutions

In the language of canon law, seminaries, colleges, hospitals, asylums, convents, etc., are usually called loca pia, pious places; that is, religious and charitable institutions. Inasmuch as all ecclesiastical institutions within a diocese, with the exception of those privileged by papal exemption , are subject to the jurisdiction of the bishop, it is evidently within his power to appoint a special or extraordinary administrator for any of these institutions, whenever he considers such a measure necessary for the welfare or the protection of such institution. It is true, the institution may, under certain conditions, appeal against the appointment of such an administrator or against the person so appointed. The Holy See having supreme jurisdiction over all institutions within the Church, may appoint administrators for any ecclesiastical institution, according to its own judgment, without recourse or appeal against its action. Administrators (executors) may also be appointed by popes or bishops to take charge of certain pious bequests and legacies made in favour of the Church or for the spiritual good of her members. Although the administration of all ecclesiastical affairs, even those of a temporal and material nature, belongs by the constitutional law of the Church exclusively to the hierarchy, yet she often allows laymen to take part in the administration of her temporalities.